The Flow Cytometry and Cell Sorting Shared Resource exists to provide investigators of the Cancer Center with access to expertise in flow cytometry and cell sorting. Open access to this facility is provided for all Cancer Center members, which obviates the need for individual laboratories to acquire this expertise or technology. Specific applications of this technology include, but are not limited to, analysis of cellular DNA content, multicolor immunofluorescence measurement, assessment of cellular-level calcium flux, detection and quantitation of uptake and efflux of fluorescent dyes, fluorescence in situ hybridization measurements from single cells, and sorting of individual cells or cell sub-populations based on any of these measurements. The facility is equipped with five flow cytometry instruments, including two high-speed cell sorters and three benchtop flow analyzers. The facility?s staff has considerable experience in the field of flow cytometry, and the services provided include consultation with users regarding experimental design and interpretation of results, sample preparation and staining by experienced technologists, processing of samples by experienced operators, and analysis of data and production of various forms of output of results. Users are also provided with access to computer workstations and flow cytometry software for data analysis. The projected total budget for this Shared Resource in year -25 of this grant is $566,395, of which 40.3% ($228,491) is requested from the CCSG; the remainder of the budget (59.7%, $337,904) will be provided by SJCRH institutional funds and by chargeback to individual investigators. More than 90% of the usage of this Shared Resource is by Cancer Center members for peer-reviewed funded projects.